Systems with film speed control and related devices, methods and computer program products

ABSTRACT

Methods, computer program products and apparatus for producing encased products using a sensor assembly that generates a signal associated with when additional sealed casing is needed based on a tautness of the sealed film proximate the sensor assembly and directs at least one servomotor to increase film-drive speed. The increase may optionally be for a short time of less than one second in response to a detected need for additional sealed casing to thereby temporarily increase casing production speed and avoid a need for an excess amount of tubular casing in a buffer.

RELATED APPLICATIONS

This application claims the benefit of and priority to U.S. Provisional Application Ser. No. 61/897,940, filed Oct. 31, 2013, the contents of which are hereby incorporated by reference as if recited in full herein.

FIELD OF THE INVENTION

The present invention relates to apparatus, systems, methods and computer program products that can seal film.

BACKGROUND OF THE INVENTION

Conventionally, in the production of consumer goods such as, for example, pasty food or non-food products, such products are pumped or stuffed into a casing in a manner that allows the casing to fill with a desired amount of the product. One type of casing is a heat-sealed tubular casing formed by sealing a thin sheet of flexible material, typically elastomeric material, into a cylindrical form. U.S. Pat. Nos. 5,085,036 and 5,203,760 describe examples of automated, high-speed contact sealing apparatus forming flat roll stock into tubular casings. The contents of these patents are hereby incorporated by reference as if recited in full herein.

It is known to configure the packaging machines to accumulate “reserve” amounts of tubular casing in a buffer with folds of tubular casing so that sufficient lengths of tubular casing are available to be pulled, stuffed and clipped in a continuous manner. U.S. Pat. No. 7,310,926, proposes methods that measure lengths of film produced and lengths of film used to attempt to control the amount of buffer, the contents of which are hereby incorporated by reference as if recited in full herein. Despite the foregoing, there remains a need for alternative control systems, particularly control systems that can reduce or substantially, if not totally, eliminate the requirement for buffers of folded/compressed lengths of casing which may not be appropriate for some casing materials and/or products.

SUMMARY OF EMBODIMENTS OF THE INVENTION

Some embodiments are directed to methods for sealing flat roll stock into shaped casing for encasing target products. The methods include: (a) forming tubular casing from flat roll stock; (b) automatically moving the tubular casing under a sealer (e.g., a heat-seal, tape seal or adhesive assembly) using a film drive assembly with drive belts powered by at least one servomotor; (c) electronically generating a signal associated with when additional sealed casing is needed using a sensor assembly residing downstream of the film drive assembly based on a tautness of the sealed film proximate the sensor assembly; then (d) electronically directing the at least one servomotor to increase film-drive speed.

The directing can be carried out to increase film drive speed for a short time of less than one second in response to a generated signal to thereby temporarily increase casing production speed and avoid a need for an excess amount of tubular casing in a buffer.

The short time can be between about 0.1 ms and 5 ms.

The increase in film-drive speed can be instantaneous with when the signal is generated. The increase in film-drive speed can be above an immediately prior average film drive speed used for automatically moving the tubular casing.

The sensor assembly can include a follower that contacts an outer surface of the tubular casing. The electronically generating can be carried out using the follower. The follower can pivot when the tubular casing increases in tautness to cause the signal to be generated to thereby indicate a need for additional sealed casing.

The sensor assembly can include an elongate flag member that reciprocates over a proximity sensor based on movement of the follower to generate the signal that causes the electronically directed increase in film drive speed.

The method can include monitoring for a number of generated signals and generating an alert when there are a plurality of signals within a defined time period to thereby indicate a potential equipment malfunction and/or need for adjustment.

The method can include monitoring for tubular casing pulled upstream of the sensor assembly using a sensor or encoder upstream of the sensor assembly in a direction closer to a clipper. The clipper has a voider assembly for providing a voiding operation on tubular packaging prior to clipping. The sensor or encoder monitors tubular casing pulled by it (over, under or to a side thereof).

The sensor or encoder can include a rotatable encoder that contacts an outer surface of the tubular casing and moves when casing is pulled under over or the side thereof. The method can include allowing operation in an intermittent or continuous run mode. In the intermittent mode, the encoder can be used to detect when tubular casing is being pulled during filling. During voiding, encoder movement is not used to direct the film drive system to supply a defined amount of tubular casing but a defined amount of tubular casing can be supplied and input from the sensor assembly can be deactivated or overridden. In the continuous mode, tubular casing can be supplied at a defined speed that is adjusted every defined number of cycles based on an amount of tubular casing used as sensed by the encoder. Film drive speed can be adjusted based on sensor assembly input associated with tubular casing tension and/or tautness. During voiding, input from the sensor assembly may be used and/or a defined length of tubular casing can be supplied to accommodate for tubular casing used during voiding.

The sensor assembly can have a follower that resides between first and second longitudinally spaced apart casing contact members held on a horn residing inside a sealed tubular casing. The electronically generating can be carried out using the follower, wherein the follower contacts an outer surface of the tubular casing and pivots when the tubular casing increases in tautness to directly or indirectly generate the signal.

The follower can include downwardly curved shape and an upper surface thereof can abut an outer surface of the tubular casing.

The first and second casing contact members can be configured to have downwardly extending lobes configured so that a lower surface of the contact members extends a greater distance beyond an outer diameter of the horn than an opposing upper surface.

Other embodiments are directed to apparatus for packaging products using tubular casings formed from flat roll stock for encasing products therein. The apparatus include: (a) a horn; (b) a forming collar residing about the horn, the forming collar configured to cooperate with a roll of flat casing material to force the flat casing material to take on a shape with long edge portions of the casing material residing proximate each other; (c) a casing sealer (e.g., a heat-seal heater, tape seal assembly or adhesive assembly) held in a distance in front of the forming collar; (d) a film drive system proximate the casing sealer, wherein the film drive system comprises at least one servomotor; and (e) a sensor assembly residing upstream of the film drive system in communication with the film drive system. The sensor assembly can be configured to generate a signal associated with an increase in tautness of tubular casing associated with a deficient amount of tubular casing relative to a tautness associated with a sufficient amount of tubular casing to cause the film drive system to increase film-drive speed.

The film drive speed can be increased for a short time of less than one second in response to a respective generated signal to thereby temporarily increase production speed and avoid a need for an excess amount of tubular casing in a buffer.

The short time can be between about 0.1 ms and about 5 ms.

The increase in film-drive speed can be instantaneous with when the signal is generated. The increase in film-drive speed is such that the speed is above an immediately prior film drive speed.

The sensor assembly can include a follower that contacts an outer surface of the tubular casing. The sensor assembly can be configured to generate the signal using the follower. The follower can pivot when the tubular casing increases in tautness to cause the signal to be generated to indicate a need for additional sealed casing.

The system may include an elongate flag member that is attached to the follower and reciprocates over a proximity sensor based on movement of the follower to generate the signal that causes the increase in film drive speed.

The system can include a controller that monitors for a number of generated signals within at least one defined time period to thereby indicate a potential equipment malfunction or need for adjustment. The controller can be configured to generate an alert when there are a plurality of detected signals with the at least one defined time period.

The system can include at least one sensor or encoder upstream of the sensor assembly to monitor when casing is pulled by it or them.

The system can include a clipper with a voider assembly residing upstream of the sensor assembly proximate a discharge end of the horn and at least one controller in (direct or indirect) communication with the at least one servomotor of the film drive assembly, the sensor assembly and the voider assembly. The at least one controller can be configured to control timing of a voiding operation to deactivate or override the sensor assembly signal during a voiding operation and to direct the film drive assembly to advance a fixed length of tubular casing during a respective voiding operation.

The system can include at least one controller configured to allow the film drive system to have selectable intermittent or continuous run modes.

The system can include first and second longitudinally spaced apart casing contact members held on the horn residing inside a sealed tubular casing proximate the sensor assembly. The sensor assembly can include a follower that contacts an outer surface of the tubular casing and pivots when the tubular casing increases in tautness to directly or indirectly generate the signal.

The follower can include a downwardly curved shape and an upper surface thereof can abut an outer surface of the tubular casing.

The first and second casing contact members can be configured to have downwardly extending lobes configured so that a lower surface of the contact members extends a greater distance beyond an outer diameter of the horn than an opposing upper surface.

The system can include a bracket assembly having laterally extending slots and longitudinally extending slots. The sensor assembly is held by the bracket assembly. The sensor assembly can include a follower that resides on one side of the bracket assembly attached to a flag member residing on an opposite side of the bracket assembly with a shaft laterally extending through a longitudinally extending slot. The bracket assembly can hold a sensor that generates a signal when the follower is pushed down by an increase in tautness of film and pivots to rotate the shaft to move the flag member over the sensor to thereby generate the signal.

The system can include a clipper with a voider assembly residing upstream of the sensor assembly proximate a discharge end of the horn. The bracket assembly can also hold an encoder at a level above the follower and at a distance apart from the follower, closer to the clipper. The encoder can reside above the horn and the follower can reside below the horn.

Yet other embodiments are directed to computer program products for operating a packaging apparatus that can accommodate different casing materials and different horn diameters to provide encased products. The computer program products can include a non-transitory computer readable storage medium having computer readable program code embodied in the medium. The computer-readable program code can include: (a) computer readable program code configured to provide a plurality of different predetermined operational modes for an apparatus that releaseably mounts different diameter horns and respective different size forming collars to supply different sized tubular casings from flat roll stock; (b) computer readable program code configured to detect a signal from a sensor assembly residing upstream of a film drive assembly having at least one servomotor that powers the film drive assembly, wherein the signal is associated with an increase in tautness of tubular casing from a tautness associated with an average production film drive speed; and (c) computer readable program code configured to direct at least one servomotor to increase film speed relative to an immediately prior film speed.

The computer readable program code to direct the at least on servomotor to increase film drive speed can be configured to increase the drive speed for a short time period to temporarily increase casing production speed.

The short time period can be between about 0.1 ms and 5 ms, and wherein the increase in film-drive speed is instantaneous with when the signal is generated.

The sensor assembly can include a follower that contacts an outer surface of the tubular casing, wherein the follower is attached to a flag member. The follower pivots when the tubular casing increases in tautness. The computer readable program code that detects a signal from the sensor assembly can be configured to detect the signal is based on when the elongate flag member moves over a proximity sensor.

The computer program product can include computer readable program code that counts generated signals within at least one defined time period to thereby indicate a potential equipment malfunction and/or need for equipment adjustment and/or to generate an alert when there are a plurality of detected signals with the at least one defined time period.

Still other embodiments are directed to packaging systems using flat roll stock sealed into shaped casing for encasing target products. The systems include a horn and a forming collar residing about the horn. The forming collar is configured to cooperate with a roll of flat casing material to force the flat casing material into a defined shape. The system includes an adhesive sealer or heat-seal sealer held a longitudinal distance in front of the forming collar and a film drive system residing proximate the adhesive sealer or heat-seal heater sealer in communication with the horn. The film drive system includes at least one servomotor. The system also includes a sensor assembly residing upstream of the film drive system in communication with the film drive system. The sensor assembly can be configured to generate a signal associated with an increase in tautness of tubular casing associated with a deficient amount of tubular casing relative to a tautness associated with a sufficient amount of tubular casing to cause the film drive system to increase film-drive speed. The system can also include at least one processor configured to detect a respective generated signal from the sensor assembly based on a tautness of the sealed film proximate the sensor assembly then instantaneously direct the at least one servomotor to increase drive speed.

It is noted that any one or more aspects or features described with respect to one embodiment may be incorporated in a different embodiment although not specifically described relative thereto. That is, all embodiments and/or features of any embodiment can be combined in any way and/or combination. Applicant reserves the right to change any originally filed claim or file any new claim accordingly, including the right to be able to amend any originally filed claim to depend from and/or incorporate any feature of any other claim although not originally claimed in that manner. These and other objects and/or aspects of the present invention are explained in detail in the specification set forth below.

These and other objects and/or aspects of the present invention are explained in detail in the specification set forth below.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a front perspective view of a packaging machine according to embodiments of the present invention.

FIG. 2 is a schematic illustration of a film speed control system according to embodiments of the present invention.

FIG. 3A is a graph of an exemplary timing diagram according to embodiments of the present invention.

FIG. 3B is a graph of another exemplary timing diagram according to embodiments of the present invention.

FIG. 3C is a graph of an exemplary speed adjustment diagram based on low supply signal input according to embodiments of the present invention.

FIGS. 4A and 4B are schematic illustrations of a film speed control system using a casing follower (e.g., dancer) according to embodiments of the present invention.

FIG. 4B illustrates the follower or “dancer” moving in response to tautness of casing relative to the position shown in FIG. 4A.

FIG. 4C is a schematic illustration of another embodiment of a film speed control circuit according to embodiments of the present invention.

FIGS. 5A and 5B are front perspective views of a packaging machine illustrating a normal position for an acceptable or sufficient supply condition (FIG. 5A) and a “short” supply position (FIG. 5B) according to embodiments of the present invention.

FIG. 6 is a front perspective view of a portion of a packaging machine illustrating the product horn and casing sensor assembly according to embodiments of the present invention.

FIG. 7A is an enlarged front perspective view of a casing sensor assembly according to embodiments of the present invention.

FIG. 7B is an enlarged rear perspective view of the casing sensor assembly shown in FIG. 7A according to embodiments of the present invention.

FIG. 8 is an enlarged side perspective view of an exemplary film drive system according to embodiments of the present invention.

FIG. 9 is a front view of a packaging machine illustrating the servomotors in position relative to the film/casing drive system according to embodiments of the present invention.

FIG. 10A is an enlarged front view of a casing sensor assembly according to embodiments of the present invention.

FIG. 10B is an enlarged rear view of the casing sensor assembly shown in FIG. 10A according to embodiments of the present invention.

FIG. 10C is an enlarged rear view of the casing sensor assembly shown in FIG. 10A, illustrating a “short supply” dancer configuration and alert arm position according to embodiments of the present invention.

FIG. 11 is a flow chart of operations that may be carried out according to embodiments of the present invention.

FIG. 12 is a block diagram of a data processing system according to embodiments of the present invention.

DETAILED DESCRIPTION

The present invention will now be described more fully hereinafter with reference to the accompanying figures, in which embodiments of the invention are shown. This invention may, however, be embodied in many different forms and should not be construed as limited to the embodiments set forth herein. Like numbers refer to like elements throughout. In the figures, certain layers, components or features may be exaggerated for clarity, and broken lines illustrate optional features or operations unless specified otherwise. The term “Fig.” (whether in all capital letters or not) is used interchangeably with the word “Figure” as an abbreviation thereof in the specification and drawings. In addition, the sequence of operations (or steps) is not limited to the order presented in the claims unless specifically indicated otherwise.

The term “concurrently” means that the operations are carried out substantially simultaneously.

The term “about” means that the noted value can vary by +/−20%.

It will be understood that when a feature, such as a layer, region or substrate, is referred to as being “on” another feature or element, it can be directly on the other element or intervening elements may also be present. In contrast, when an element is referred to as being “directly on” another feature or element, there are no intervening elements present. It will also be understood that, when a feature or element is referred to as being “connected”, “attached” or “coupled” to another feature or element, it can be directly connected to the other element or intervening elements may be present. In contrast, when a feature or element is referred to as being “directly connected”, “directly attached” or “directly coupled” to another element, there are no intervening elements present. The phrase “in communication with” refers to direct and indirect communication. Although described or shown with respect to one embodiment, the features so described or shown can apply to other embodiments.

The term “circuit” refers to software embodiments or embodiments combining software and hardware aspects, features and/or components, including, for example, at least one processor and software associated therewith embedded therein and/or executable by and/or one or more Application Specific Integrated Circuits (ASICs), for programmatically directing and/or performing certain described actions, operations or method steps. The circuit can reside in one location or multiple locations, it may be integrated into one component or may be distributed, e.g., it may reside entirely in or supported by a workstation or cabinet (e.g., HMI of a machine) or single computer, partially in one workstation, cabinet, processor or computer, or totally in a remote location away from a local computer, processor, workstation or cabinet. If the latter, a local computer and/or processor can communicate over a LAN, WAN and/or internet to transmit instructions and/or data.

The terminology used herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention. As used herein, the singular forms “a,” “an” and “the” are intended to include the plural forms as well, unless the context clearly indicates otherwise. It will be further understood that the terms “comprises” and/or “comprising,” when used in this specification, specify the presence of stated features, steps, operations, elements, and/or components, but do not preclude the presence or addition of one or more other features, steps, operations, elements, components, and/or groups thereof. As used herein, the term “and/or” includes any and all combinations of one or more of the associated listed items.

As used herein, phrases such as “between X and Y” and “between about X and Y” should be interpreted to include X and Y. As used herein, phrases such as “between about X and Y” mean “between about X and about Y.” As used herein, phrases such as “from about X to Y” mean “from about X to about Y.”

Unless otherwise defined, all terms (including technical and scientific terms) used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. It will be further understood that terms, such as those defined in commonly used dictionaries, should be interpreted as having a meaning that is consistent with their meaning in the context of the relevant art and should not be interpreted in an idealized or overly formal sense unless expressly so defined herein.

The term “frame” means a generally skeletal structure used to support one or more assemblies, modules and/or components. The frame can be a floor mount frame. The term “automated” means that operations can be carried out substantially without manual assistance, typically using programmatically directed control systems and electrical and/or mechanical devices. The term “semi-automatic” means that operator input or assistance may be used but that most operations are carried out automatically using electromechanical devices and programmatically directed control systems.

In the description of embodiments of the present invention that follows, certain terms are employed to refer to the positional relationship of certain structures relative to other structures. As used herein, the term “front” or “forward” and derivatives thereof refer to the general or primary direction that the filler or product travels in a production line to form an encased product; this term is intended to be synonymous with the term “downstream,” which is often used in manufacturing or material flow environments to indicate that certain material traveling or being acted upon is farther along in that process than other material. Conversely, the terms “rearward” and “upstream” and derivatives thereof refer to the directions opposite, respectively, the forward and downstream directions.

The term “servomotor” refers to a closed-loop servomechanism with an electric motor that uses electronic feedback to control its operation. The control can be automatic rather than manual. The servomotor comprises the electric motor, at least one encoder, a controller and driver. The servomotor components can be integrated into a unitary package or distributed. The driver compares a position command and the encoder position/speed information and controls the drive current for the electric motor. The input to the controller includes a signal, either analog or digital, representing the position commanded for the output shaft of the motor. The measured position of the output can be compared to a command position and an external input to the controller. The servomotor can be configured to measure both the position and the speed of the output shaft. The speed of the motor is controlled and, except potentially during short bursts or times, does not run at full-speed during normal operation. The servomotor can operate with a PID protocol to allow the servomotor to be brought to its commanded position more quickly and more precisely. PID controllers can make use of a speed signal. The servomotor encoder can comprise an optical encoder, absolute or incremental, to determine position at power-on. Incremental systems may combine their inherent ability to measure intervals of rotation with a simple zero-position sensor to set their position at start-up. The electric motor can be DC or AC. In some embodiments, the servomotors can be an electronically-commutated brushless motor. In some embodiments, the servomotor can be an AC induction motors with variable frequency drive that allows for control of its speed. In some embodiments, the servomotor is a brushless AC motor with permanent magnet fields.

The present invention is particularly suitable for producing encased products that may also employ closure clips to seal products held in the casings. The product may be a linked chain of elongated pumped, flowed or extruded product held in a casing. The casing can be any suitable casing (edible or inedible, natural or synthetic) such as, but not limited to, collagen, cellulose, plastic, elastomeric and/or polymeric casing. Typically, the casing material comprises planar roll stock of film comprising elastomeric and/or polymeric material. The elastomeric and/or polymeric sheet material is a relatively thin sheet (or film) of roll-stock that can be formed in situ into a continuous length of heat-sealed and/or otherwise joined or seamed tubular casing. Embodiments of the invention are configured to seal laminated or multi-layer films. The multi-layer films can comprise different materials, typically one material as a first layer and a second material as an overlying second layer. The different materials can be laminated or one layer can be a coating such as a metalized spray coating. The laminated or multi-layer films can include “foil film”, metalized polymeric and/or elastomeric films, such as aluminized plastic and/or aluminized polymeric films. In some embodiments, the films can comprise heat-shrink films.

The term “film” means the material is thin. The thickness is typically under about 0.5 mm, such as in a range of between about 0.02 mm to about 0.3 mm, typically between about 0.03 mm to about 0.13 mm. In some embodiments, the film can have a thickness that is about 0.03 mm, about 0.04 mm, about 0.05 mm, about 0.06 mm, about 0.07 mm, 0.08 mm, about 0.09 mm, about 0.10 mm, about 0.11 mm, about 0.12 mm, about 0.13 mm, about 0.14 mm, about 0.15 mm, about 0.16 mm, about 0.17 mm, about 0.18 mm, about 0.19 mm, about 0.20 mm, about 0.25 mm, about 0.30 mm and the like. However, the casing can have other thicknesses.

The forming can be carried out substantially automatically and intermittently and/or continuously over a desired interval, typically between at least about 45-60 minutes, depending on the size of the length of the roll stock, pump speed and film drive speed, for example. The sealing can be performed using a heat seal. The seal can seal a seam formed by joining two outer long sides of the casing/film. The seam can be a flat, fin, or other overlapping and/or abutting joint configuration.

The encased elongated or tubular product can be an elongated food product. Exemplary meat products include, but are not limited to, strands of meat (that may comprise pepperoni, poultry, and/or beef or other desired meat), and processed meat products including whole or partial meat mixtures, including sausages, hotdogs, and the like. Other embodiments of the present invention may be directed to seal other types of food (such as cheese) or other product in casing materials. Examples of other products include pasty products such as caulk or powders such as granular materials including grain, sugar, sand and the like or other flowable materials including wet pet food (similar to that held conventionally in cans) or other powder, granular, solid, semi-solid or gelatinous materials including explosives. Thus, embodiments of the invention can be used for packaging target products for any industry including food, aquaculture, agriculture, environmental, building or home maintenance supplies, chemical, explosives, or other applications.

The term “instantaneous” means that the increase in speed occurs essentially at the same time as a sensor signal associated with a low tubular casing is generated and/or detected, typically within about 0.1 second, typically within about 0.01 seconds or less thereof.

Turning now to FIG. 1, an exemplary packaging apparatus 10 configured to form tubular casings is shown. The apparatus 10 includes a (heat-seal) horn 20, a forming collar 30, a heat-seal assembly 40 (also called a “heat-seal heater”), a casing drive assembly 45 (which will be referred to hereafter as a “film” drive assembly), a casing sensor assembly 100 and optionally at least one pre-heater 50.

To be clear, the term “film drive assembly” refers to drive assemblies that drive any casing material on the apparatus, not just film.

While the figures illustrate a heat-seal heater 40 for forming the seal on the casing, it is also contemplated that other sealing assemblies can be used rather than or with the heat-seal heaters, including, for example, adhesive (heated) or tape seal systems as is known to those of skill in the art. Also, while shown with respect to a single clipper system, the packaging system can be a multi-clipper system. See, e.g., U.S. Pat. No. 8,006,463, the contents of which are hereby incorporated by reference as if recited in full herein.

The system 10 typically also includes a clipper 75 and voiders V that cooperate with the clippers to void filling in a tubular package to allow the clipper 75 to apply one or more clips to a filled package to seal a respective package.

FIG. 2 illustrates that the apparatus 10 can include or be in communication with a controller 500 that is in communication with the casing sensor assembly 100 and at least one servomotor 200. The servomotor(s) 200 is in communication with the film drive assembly 45 to be able to control casing/film drive speed. The film drive assembly 45 and/or the controller 500 can be in communication with the sealer 40 (e.g., heat-seal heater, tape seal assembly or adhesive seal assembly).

The apparatus 10, using the sensor assembly 100 and at least one servomotor 200 (FIGS. 2, 8 and 9) in communication with the film drive assembly 45, can be configured to operate without requiring a large buffer B (FIG. 5A) of sealed tubular casing F. In some embodiments, no buffer B is required. In some embodiments, a limited amount of buffer B is used.

In some embodiments, the system 10 can be configured to produce a small excess amount of tubular sealed casing at the beginning of each roll of flat stock, e.g., between about 1-2 inches. In other embodiments, the system 10 can be configured to only produce what is used for each clip cycle or slightly less and the sensor assembly 100 can be used to determine when the tubular casing F is taut to have the system 10 produce additional tubular casing instantaneously when needed.

The system 10 can have a normal operating speed that can be sped up in situ automatically based on the sensor assembly 100 detecting when an amount of tubular film is short of a desired amount based on a tautness of the tubular casing proximate the sensor assembly 100. The sensor assembly 100 can be configured to contact the tubular casing F between the film drive assembly 40 and the discharge end of the horn 20 d and generate a signal that identifies when there is a low or insufficient amount of tubular casing.

In some particular embodiments, the system 10 can operate without requiring a buffer B of tubular film F. In this embodiment, the tubular film F can be supplied so that it has only a sufficient length or slightly under a sufficient length needed for voiding and clipping to form a particular length of product, but not a length that is in excess of the amount needed for a particular length of product.

The system 10 can be configured to inhibit or disallow undue amounts of wrinkle or fold formation (e.g., “crinkling”) in the supplied formed tubular casing. This tight control can avoid creases, microfissures, cracks and/or microfractures in fragile casings such as laminated aluminum films.

The film speed and other operational parameters can be selected at set-up. The machine 10 can supply tubular casing F at a defined speed range that can be determined or identified at set-up. This speed can be controlled to produce sealed tubular casing F in respective lengths corresponding to amounts to be successively filled and clipped, but there can be variation during production depending on density of the product, speed of the pump, casing type, product length and speed of the film drive and heat-seal assemblies and the like.

As shown in FIG. 2, the system 10 can include a controller 500 that communicates with the film sensor assembly 100 and a servomotor 200 to be able to increase the speed of the film drive assembly 45 from a preset or normal drive speed for short times, such as between about 0.1 ms to about 5 ms, in response to each identified “low” film signal input from the sensor assembly 100. The short time may be under 1 second, such as, for example, between about 0.1 ms to about 5 ms, including about 0.2 ms, about 0.3 ms, about 0.4 ms, about 0.5 ms, about 0.6 ms, about 0.7 ms, about 0.8 ms, about 0.9 ms, about 1 ms, about 1.5 ms, about 2 ms, about 2.5 ms, about 3 ms, about 3.5 ms, about 4 ms, about 4.5 ms and about 5 ms.

FIG. 3A illustrates an exemplary timing graph of sensor low film input with a corresponding servomotor increase speed mode. The increase speed mode can be essentially instantaneous, if not instantaneous, response to a low film signal and can be operated with relatively brief “on” periods corresponding to the low film signal then “off” periods for normal speed. Thus, as shown in FIG. 3A, in some embodiments, the system 10 can have a normal (average) operating film drive speed S_(N) per product type and/or product size that can be increased S_(I) in situ automatically based on the casing sensor assembly 100 responding to (e.g., generating and detecting) an increase in tension associated with the tubular casing supply being insufficient or short.

In some embodiments, the low supply signal can be used to automatically adjust average operating film speed S_(N), particularly where successive low supply signals are generated within a defined (e.g., short) time frame. In some embodiments, the signal can generate a change in speed that has an instantaneous “burst” or greatly increased first speed for a short time period S_(I), followed by reduced speed from the first increased speed but that is a small increase above a prior running average film drive speed S_(N)i as shown in FIG. 3C, for example.

The duration of the increase and/or the increase in speed itself can be predefined and can vary by product type, size, casing material, filling speed and the like. The duration can be for a short time interval and/or may be carried out to increase average film drive speed.

The increase in speed S_(I) of the film drive assembly 45 can be any suitable increase. In some particular embodiments, it is contemplated that the increase may be between about 1%-200% more than S_(N). S_(I) may be, for example, about 1%, about 2%, about 3%, about 4%, about 5%, about 6%, about 7%, about 8%, about 9%, about 10%, about 15%, about 20%, about 30%, about 40%, about 50% or more such as about 100%, about 150% or about 200% above S_(N). The increase in speed can be for a short time period. The increase in speed can be to increase the average film drive speed. The latter may be for normal operation or used when successive low supply signals may be detected/generated within a defined time interval.

The short time interval for increase in speed can be any suitable interval, typically under about 1 second. In some embodiments, the short time interval of increased speed may be between about 0.1 ms to about 5 ms, for example.

The duration of the increase in film speed can vary or be the same over a roll of film stock. The amount of increase in film speed can vary or be the same over a roll of film stock. For example, if two low signals are received within a short amount of time, the increase in film speed may be increased from the first increase in speed and/or the duration may increase from the first increase speed period. Repeat low supply signals may also be used to indicate a need (or cause an adjustment of speed) for average film speed operation.

FIG. 3A illustrates that the sensor assembly 100 can generate a signal indicating film/casing supply at the sensor assembly 100 is low at t₁, t₂, and t₃, for example, and, in response to this signal, an instantaneous short increase in film drive speed associated with servomotor output occurs.

FIG. 3B illustrates that, in some embodiments, the apparatus 10 can operate so that film drive speed is adjusted based on voider operation V. The pump P may also be slowed or stopped during a voiding operation. The sensor assembly 100 may be disregarded or inactivated during a voiding operation.

FIG. 4A illustrates an example of the sensor assembly 100 at a normal film speed and sufficient supply while FIG. 4B illustrates the sensor assembly 100 sending a signal that there is insufficient supply and/or a need for increased film speed. The sensor assembly 100 can include a casing follower (also called a “dancer”) 105. The follower 105 resides external of the tubular casing downstream of the film drive system 45. FIG. 4B illustrates the follower 105 moved by the casing F contacting the follower 105 when the casing F is taut.

The sensor assembly 100 can be configured to generate a signal to the control circuit 100 c such as to the controller 500 and/or directly to the servomotor 200 to increase film drive speed because more casing/film is needed.

FIG. 4B illustrates that the “low” supply and/or tubular casing F “tension” signal can be based on a movement of the follower 105 in response to a tautness of the film at the follower 105 rather than an actual measurement of tension of the tubular casing F.

The follower 105 can reside to the side or above the casing F and horn 20 rather than below the casing F and horn 20 as shown.

FIG. 4C illustrates another embodiment where the sensor 130′ can be placed on a casing contact member 122 that resides inside and can contact the casing F. The sensor 130′ can include a pressure or force sensor such as a piezoelectric sensor, a piezoresistive pressure sensor, a monocrystalline silicon pressure sensor, a thin film pressure sensor, a capacitive or resistive transducer and the like. The sensor 130′ can include a single component or a plurality of (e.g., two closely spaced) cooperating components. If the latter, one or both of the components can stretch, move apart or elongate when tautness of the tubular casing F thereon increases (typically above a defined level). The sensor 130′ can contact the tubular casing F and can generate a signal that can be sent to the controller 500 (and/or directly to the servomotor 200) to increase film drive speed S_(I). The sensor 130′ can be wireless or hard-wired to a circuit 100 c for servomotor control. If the latter, the wiring can be directed along the horn 20 toward the forming collar 30 to the circuit 100 c connection.

The system 10 can be configured to generate an alert or to stop filling and casing/film production if too many sensor assembly low supply signals are generated within a defined time period, e.g., 2 or more in under about 30 seconds to about 1 minute, or more than a plurality e.g., more than 3 in 5 minutes, for example, as such can indicate a problem with the belt drive, for example.

FIGS. 4A and 4B schematically illustrate that the sensor assembly 100 can include a casing (e.g., film) follower 105 that can move up and down with respect to looser (FIG. 4A) or tighter (FIG. 4B) amounts of tubular casing F (e.g., film with increased tension) residing proximate thereto. A sensor 130 can detect a change in position of a flag member 125 based on movement of the follower 105. The controller 500 can detect the low supply signal 130 s (FIG. 4B) from the sensor 130 and direct the servomotor 200 to increase speed. The sensor 130 can be any suitable sensor that can generate a signal to indicate when a short supply condition exists to cause the servomotor to increase speed. The sensor signal can be generated using contact or non-contact sensor signal. The sensor 130 can include one or more of a proximity switch (such as a Hall-Effect sensor), an electrical or optical encoder, a pressure or force sensor, a break in a light (e.g., laser) signal between a laser or light transmitter and a receiver, an acoustic sensor or other suitable signal generating device.

The follower 105 is shown as indirectly generating the “low film” or “increase speed” signal using the flag member 125. However, it is contemplated that in some embodiments, the movement of the follower 105 can directly trigger the signal based on detection of the movement of the follower itself without requiring the flag member. Thus, the system 10 can be configured to electronically detect movement of the follower based on increases in tautness to directly generate the signal using an optical or other encoder or sensor or camera, for example.

As shown in FIGS. 4A, 4B, and 6, the sensor assembly 100 can cooperate with at least one casing contact member 122, shown as first and second longitudinally spaced apart casing contact members 122 ₁, 122 ₂ on the product horn 20. The members 122 are shown as disks or collars but can have other configurations. The members 122 can have the same or different configurations. The casing contact members 122 can encase the horn 20 as shown or reside over only about a portion of the outer diameter of the horn, e.g., circumferentially extend between about 90-180 degrees, for example. As shown, the follower 105 can reside proximate the casing contact member 122 outside the casing F. Where the first and second longitudinally spaced apart casing contact members 122 ₁, 122 ₂ are used, the follower 105 resides between them, typically longitudinally centered, but the follower 105 may reside closer to one than another.

In some embodiments, the casing contact members 122 may be substantially flush with the outer diameter of the horn at the upper surface of the horn 20 u and may be configured with lobes 122 l that extend a distance beyond the diameter of the horn at a bottom surface of the horn 20 b as shown in FIG. 9.

Although shown as two casing contact members 122, in some embodiments, a single member may be used.

The outer diameter of the member 122 can be configured to define an outer diameter of the target filled tubular product, e.g., where a four inch tubular product is produced, the casing contact members 122 have an outer diameter of about 4 inches (typically just above this value). The casing contact members 122 may project a distance below (or above if the follower 105 resides above the horn) an outer diameter of the horn 20 or where integrated into the horn, relative to a diameter of the horn upstream and downstream thereof.

Where first and second casing contact members 122 ₁, 122 ₂ are used, they can be spaced apart a defined distance. This spacing and the distance “D” from the discharge end of the horn 20 d (FIG. 6) can be adjusted or vary depending on the product, casing, pump speed, film speed, size of the horn and the like. The members 122 can be integral to the horn 20 or can be separate components attached to the horn 20. The casing contact members 122 can have an outer surface that has reduced friction, e.g., may have a lubricious coating or material to facilitate the tubular casing F sliding thereover.

FIGS. 5A and 5B illustrate, respectively, the packaging system 10 with a “normal” suitable length casing supply and “low” casing supply that can be detected by the sensor assembly 100. In some embodiments, the system 10 can be configured to include a small excess amount of tubular casing or buffer B that allows a loose configuration or successive fold. The buffer B can reside between the film drive assembly 45 and the sensor assembly 100 (FIG. 5A). The film folds F in the buffer B can be provided by the machine 10 so that tubular casing F can be sealed to have a small reserve at initiation of a packing/filling cycle (FIG. 5A) and/or at other times during the packaging to assure that there is sufficient casing/film sealed F for filling. FIG. 5B illustrates that the buffer B can be depleted but the sensor assembly 100 can identify this situation and generate a signal to cause the film drive assembly 45 to immediately increase film-drive speed for a short duration. The buffer B and/or sensor assembly 100 can inhibit the machine 10 from running out of sealed film F while successive products are stuffed.

With some casings, the machine 10 can run with a generous amount of buffer B. However, some types of casing/film are susceptible to damage if the casing/film gets bunched up and creased. The sensor assembly 100 can allow the packaging machine to have an intermittent operation to avoid excess or any bunching of susceptible films.

In some embodiments, the system 10 can be configured to selectively operate in either a continuous mode or an intermittent mode.

In some embodiments, the system 10 may optionally include an encoder or sensor 145 residing proximate the sensor assembly 100. The encoder or other sensor 145 can help set an appropriate average drive speed of the film drive system 45 during filling. That is, the encoder or sensor 145 can detect when tubular casing F is supplied (e.g., pulled thereunder) by the drive assembly 45 and cooperating heat seal assembly 40.

In some embodiments, the encoder or sensor 145, where used, can reside upstream of the heat-seal assembly 40 and typically also upstream of the casing sensor assembly 100. The encoder or sensor 145 can be used to detect when tubular casing F is being pulled forward during a respective filling process.

As is well known to those of skill in the art, during voiding, the tubular casing F can be pulled abruptly forward (e.g., jerked rapidly upstream by voiders V) in front of the discharge end of the horn 20 d when the voiders V close and separate. This action can impair or destroy the heat-seal on the tubular casing if sufficient force is applied to the film upstream, against the pull direction of the voiders. In some embodiments, during voiding, the system 10 can be synchronized to disregard or inactivate the sensor assembly 100 and/or encoder or sensor 145 and instead provide a defined length/amount of casing from the film drive assembly 45 to accommodate for the amount of casing used during voiding, rather than using input from the encoder or sensor 145. The amount or length of casing supplied during voiding can vary depending on the casing material, the horn size, pump speed, film drive assembly speed and the product. Although the encoder or sensor 145 is shown in FIGS. 1, 7A and 7B as a rotating contact-encoder, other sensors or contact encoders or non-contact sensors or encoders of any variety may also be used.

The voiding operation of the voiders V can be detected using a sensor such as a proximity or position sensor of any type and/or based on input from a controller which may be controller 500 (FIG. 2) and/or controller for the HMI (FIG. 1) that directs the voiding operation.

In a continuous mode, the tubular casing F can be supplied at a set speed that can be automatically adjusted every defined “x” number of cycles based on the amount of casing used as detected by the encoder or sensor 145 and/or based on a number of “tautness-induced” insufficient supply (flag) signals being indicated by the sensor assembly 100.

FIGS. 7A and 7B illustrate an exemplary embodiment of a sensor assembly 100. As shown, the assembly 100 includes the follower 105 and the follower arm 108. The follower arm 108 is attached to a shaft 108 s that extends orthogonal to the arm 108. The shaft 108 is fixedly attached to a hub 109. The hub 109 can be held in a bearing flange 129 to facilitate movement (rotation back and forth) of the proximity flag 125 over the sensor 130. When the follower 105 moves down, the arm 108 pivots about the shaft axis 108 s at pivot 108 p, causing a proximity flag member 125 to move over a sensor 130, shown as a proximity switch 130 p. The proximity switch 130 p can have between a 4 mm to 12 mm range.

The shaft 108 and hub 109 can be held in a bracket 117 with an upwardly extending slot 117 s with a height “H” that allows the follower 105 to be positioned at an adjustable height depending on the size horn in use. The bracket 117 can cooperate with adjuster bars 127 (FIG. 7B) that secure the follower 105 at a desired position. The bracket 117 can also include horizontal (longitudinally extending) channels 117 c that allow for longitudinal positional adjustment.

The bracket 117 can be held by a main (plate) bracket 112 to allow the positional adjustment to accommodate different diameter horns 20. The main bracket 112 can also hold the encoder 145. The main bracket 112 can cooperate with an encoder clamp plate 145 c in a slot for height adjustment. The main bracket 112 can hold an encoder mounting bracket 145 b in slot 112 s to allow for height adjustment of the encoder 145. As shown, the encoder 145 is a rotary contact encoder. However, as discussed above, other encoder or film movement sensor may be used.

The film follower 105 can have any suitable configuration but is shown in FIGS. 6, 7A and 7B as having a rounded or arcuate upper surface 105 u that extends laterally across at least a major portion of the horn diameter thereat. The follower 105 can have a width (laterally extending) dimension that is between about 0.5-4 inches, for example.

The casing F can be a multi-layer film comprising at least two different materials and/or may comprise an aluminum coating that may be sensitive to sharp bends or folds.

Referring to FIG. 8, the film drive assembly 45 can optionally include vacuum drives with belts 45 b that contact opposing sides of the casing on the horn 20 to pull the tubular casing forward toward the sensor assembly 100 and discharge end of the horn 20 d. The film drive assembly 45 can be configured to operate with an adjustable drive speed to pull flat stock casing/film F from a roll of flat stock over the collar 30 and through the heat-seal assembly 40 to form tubular casing.

As also shown, two servomotors 200 can be used and may be synchronized to have the same speed at the same time. However, a single servomotor 200 can also be used with appropriate gearing and belts, links or other drive inputs from the motor to the film belts 45 b. Further, the servomotors 200 can be configured to extend upwardly below the vacuum belts 45 b as shown. Alternatively, the servomotor(s) 200 can extend above the belts 45 and even to the sides of respective belts 45 b using appropriate gear boxes to direct the rotational input to the belts 45 b.

FIG. 9 illustrates the horn 20 with the members 122 ₁, 122 ₂ and film drive assembly 45 with servomotors 200 upstream of the forming collar 30 and an optional pre-heater 50, all held by a housing 10 h so that the discharge end of the horn 20 d extends out of the housing 10 h.

The drive speed can be such that the casing F is advanced over the forming collar 30 and through the heat-seal heater 40 at a speed that is typically between about 20-400 ft/min, more typically between about 20-300 ft/min or between about 20-150 ft/min. In the upper end of this range, e.g., at about 150 ft/min, the long ends of the casing are typically under the heat-seal heater 40 for a short time of between about 0.1 second to about 0.5 seconds. At a rate of about 150 ft/min, the exposure to the heat-seal heater 40 is about 0.2 seconds.

In some embodiments, the heat-seal assembly 40 can comprise a heat-band heater that uses a continuously rotating (endless) heat seal-band 40 b to seal the seam. U.S. Pat. Nos. 5,085,036 and 5,203,760 describe examples of automated, high-speed contact sealing apparatus forming flat roll stock into tubular film casings. The contents of these patents are hereby incorporated by reference as if recited in full herein. However, it is contemplated that other heat-seal heater configurations or other seal systems may be used. For example, adhesive seal or tape seal systems can be used with or without heat-seal assistance. Where used, the heat-seal heater 40 can comprise rollers or other contact-based seal mechanisms.

Referring to FIGS. 10A-10C, the proximity flag member 125 can rotate back and forth in response to movement of the follower 105 up and down. FIG. 10A illustrates the follower 105 in a normal operative orientation while FIG. 10B illustrates a position of the flag member 125 over the sensor 130. FIG. 10C illustrates the follower 105 pushed down with a responsive movement of the flag member 125 away from the sensor 130, thereby generating a “low supply” and/or “increase speed” signal. FIGS. 10B and NC show that the flag member 125 can reciprocate in a longitudinal direction but other configurations and orientations may be used. Also, in this embodiment, when the sensor 130 does not detect the flag member 125, the “increase film drive speed” signal is generated. However, the system 10 can be configured to operate in a reverse configuration so that when the proximity sensor senses the flag member 125, the “increase drive speed” signal can be generated.

In some embodiments, a pulse signal that is externally applied (when it is the pulse input type) and the rotation detected by the servomotor encoder, are counted and the difference (deviation) is outputted to the speed control unit. This counter is referred to as the deviation counter. During motor rotation, an accumulated pulse (positioning deviation) is generated in the deviation counter and is controlled so as to go to zero. The (position holding by servo control) function for holding the current position is achieved with a position loop (deviation counter).

The forming collar 30 can also be held in a different orientation from that shown in FIGS. 1, 6, and 9, e.g., rotated to direct the flat casing long edges together along an outer side or the bottom with the heat seal heater 40 residing to the side or under the horn 20, respectively.

As noted above, the controller 500 can be configured as or be in communication with a proportional-integral-derivative controller (PID controller) to have a control loop feedback mechanism for varying current or power to the servomotor(s) 200 to maintain a speed and rapidly (instantaneously) increase then decrease speed.

The apparatus 10 can form part of a packaging system that includes a shined voiding/clipping apparatus located downstream of a respective horn and heat seal assembly 40 to produce an elongated product. The product can be produced in a linked chain of tubular or chub product with clips applied at desired intervals. The length and diameter of each link, chub or discrete product and/or the overall length of the chain can vary depending on the type of product being produced. Examples of typical strand or chain lengths are between about 1-6 feet. See, e.g., U.S. Pat. Nos. 3,543,378, 5,167,567, 5,067,313, and 5,181,302, the contents of which are hereby incorporated by reference as if recited in full herein.

The apparatus 10 can be configured to interchangeably accommodate different size horns 20 and corresponding different size forming collars 30 that form the suitable size casing. For example, the diameters of the horns 20 can range between about ¼ inch to about 8 inches, typically between ¾ inches to about 5 inches in defined size increments of ¼ inch, ½ inch or 1 inch, for example. The forming collar 30 will have a width that is larger than the corresponding horn and typically has about a 3× width as the corresponding diameter of the tubular casing. The casing contact member(s) 122 can vary in size and/or shape based on the diameter of the horn 20 and/or target product size.

The horn 20 can be configured as internal and external cooperating horns. For example, the internal horn can have a length that extends through an external heat seal horn 20 h (FIG. 9). The heat seal horn 20 h resides at least under the heat seal assembly 40. The horn 20 may be a single horn that can have a different external shape at the forming collar and/or heat seal assembly 40, such as a flat surface aligned with the heat seal band to facilitate heat seal operation.

Examples of exemplary devices and apparatus used to void, clip or tension casing material are described in U.S. Pat. Nos. 4,847,953; 4,675,945; 5,074,386; 5,167,567; and 6,401,885, the contents of which are hereby incorporated by reference as if recited in full herein. Generally stated, clips can be applied to the casing material to wrap around and close or seal the product therein. The seal formed by the clip against the casing may be sufficiently strong so as to be able to hold a vacuum of about 16 mm Hg for about 24-48 hours. Examples of suitable clips include metallic generally “U”-shaped clips available from Tipper Tie, Inc., in Apex, N.C. Other clips, clip materials and clip configurations may also be used.

FIG. 11 illustrates a method of steps or actions that can be used to carry out embodiments of the present invention. Tubular sealed casing is provided (e.g., film) (block 300). Optionally, the flat roll stock casing material can be pulled through a forming collar to form a shaped tubular casing and long edges of the casing material can be sealed together after the forming collar to provide the tubular sealed casing (block 302).

The method can electronically (i) detect when additional sealed film is needed (block 310) and (ii) direct a servomotor to increase film-seal speed (block 320).

The increase can be for a short duration of time under 1 second, typically under 0.2 seconds such as between about 0.1 ms and about 5 ms, and/or may be to define an adjusted average “running” or production speed.

The method can optionally use a sensor or encoder residing upstream of a casing dancer to control average film speed during filling (block 303).

The servomotor can create an instantaneous increase, then decrease, in casing/film drive speed to temporarily produce additional heat-seal casing/film to thereby produce sufficient casing/film for use (block 322).

The creating step can be carried out without producing excess tubular casing/film to avoid creating or adding to a buffer (block 324). Where used, the buffer can be relatively short, e.g., between about 1-2 inches that can be created at the beginning or at different defined times for a single supply of roll stock.

The method can electronically allow intermittent and continuous film run modes (block 326).

The detecting can be carried out using a casing follower that resides external of and proximate to tubular casing downstream of the casing/film drive assembly (block 312).

A signal can be generated to indicate when a short supply condition exists to cause the electronically directing action (block 314). The signal can be generated using a proximity switch, encoder, sensor or other suitable signal generator.

The casing follower or dancer can be configured to contact and pivot in response to tautness of casing/film thereat (block 315).

The casing follower can be in communication with an elongate arm that moves in response to the pivoting of the follower to generate a flag signal of “short supply” to cause the servomotor to increase film/casing drive speed (block 317). The increase may be for a short time that may be under 1 second, such as, for example, between about 0.1 ms to about 5 ms, including about 0.2 ms, about 0.3 ms, about 0.4 ms, about 0.5 ms, about 0.6 ms, about 0.7 ms, about 0.8 ms, about 0.9 ms; about 1 ms, about 1.5 ms, about 2 ms, about 2.5 ms, about 3 ms, about 3.5 ms, about 4 ms, about 4.5 ms and about 5 ms.

At least one clip can be applied to at least one end portion(s) of a filled length of the sealed casing/film to thereby seal an end of the filled tubular package (block 328).

FIG. 12 is a block diagram of exemplary embodiments of data processing systems 405 in accordance with embodiments of the present invention. The processor 410 communicates with the memory 414 via an address/data bus 448. The processor 410 can be any commercially available or custom microprocessor. The memory 414 is representative of the overall hierarchy of memory devices containing the software and data used to implement the functionality of the data processing system 405. The memory 414 can be non-transitory, and can include, but is not limited to, the following types of devices: cache, ROM, PROM, EPROM, EEPROM, flash memory, SRAM, and DRAM.

As shown in FIG. 12, the memory 414 may include several categories of software and data used in the data processing system 405: the operating system 452; the application programs 454; the input/output (I/O) device drivers 458; an Automated Servomotor Speed Adjustment Module 450 and the data 456.

The data 456 may include a look-up chart of different casing run times (i.e., for tubular elastomeric (polymer) casings formed in situ, as well as the product, filling rates, selectable chain lengths and link lengths and the like corresponding to particular or target products for one or more producers.

As will be appreciated by those of skill in the art, the operating system 452 may be any operating system suitable for use with a data processing system, such as OS/2, AIX, DOS, OS/390 or System390 from International Business Machines Corporation, Armonk, N.Y., Windows CE, Windows NT, Windows95, Windows98 or Windows2000 from Microsoft Corporation, Redmond, Wash., Unix or Linux or FreeBSD, Palm OS from Palm, Inc., Mac OS from Apple Computer, LabView, or proprietary operating systems. The I/O device drivers 458 typically include software routines accessed through the operating system 452 by the application programs 454 to communicate with devices such as I/O data port(s), data storage 456 and certain memory 414 components. The application programs 454 are illustrative of the programs that implement the various features of the data processing system 405 and preferably include at least one application which supports operations according to embodiments of the present invention. Finally, the data 456 represents the static and dynamic data used by the application programs 454, the operating system 452, the I/O device drivers 458, and other software programs that may reside in the memory 414.

While the present invention is illustrated, for example, with reference to the Module 450 being an application program in FIG. 12, as will be appreciated by those of skill in the art, other configurations may also be utilized while still benefiting from the teachings of the present invention. For example, the Module 450 may also be incorporated into the operating system 452, the I/O device drivers 458 or other such logical division of the data processing system 405. Thus, the present invention should not be construed as limited to the configuration of FIG. 12, which is intended to encompass any configuration capable of carrying out the operations described herein.

The I/O data port can be used to transfer information between the data processing system 405 or another computer system or a network (e.g., the Internet) or to other devices controlled or directed by the processor 410. These components may be conventional components such as those used in many conventional data processing systems which may be configured in accordance with the present invention to operate as described herein.

For example, the data processing system 405 can be a computer program product with computer readable program code configured to provide a plurality of different predetermined operational modes. In particular embodiments, the computer readable program code is configured to accept user input to identify the type of casing material selected for deployment and/or a selection of the size of the horn or tubular casing. In addition, the computer readable program code can be configured to inhibit operation until the door of the machine is closed.

In addition, the computer readable program code can be configured to automatically identify when a casing supply is exhausted. For example, the computer readable program code can be configured to monitor and/or detect when a limit switch is triggered responsive to force applied to a lead attached to a trailing edge portion of the supply of casing material as the trailing edge portion of the casing material advances.

While the present invention is illustrated, for example, with reference to particular divisions of programs, functions and memories, the present invention should not be construed as limited to such logical divisions. Thus, the present invention should not be construed as limited to the configuration of FIG. 12 but is intended to encompass any configuration capable of carrying out the operations described herein.

The operation and sequence of events can be controlled by a programmable logic controller. The operational mode can be selected by an operator input using a Human Machine Interface to communicate with the controller as is well known to those of skill in the art.

The flowcharts and block diagrams of certain of the figures herein illustrate the architecture, functionality, and operation of possible implementations of selective implementation of single and dual clip closure means according to the present invention. In this regard, each block in the flow charts or block diagrams represents a module, segment, or portion of code, which comprises one or more executable instructions for implementing the specified logical function(s). It should also be noted that in some alternative implementations, the functions noted in the blocks may occur out of the order noted in the figures. For example, two blocks shown in succession may in fact be executed substantially concurrently or the blocks may sometimes be executed in the reverse order, depending upon the functionality involved.

The foregoing is illustrative of the present invention and is not to be construed as limiting thereof. Although a few exemplary embodiments of this invention have been described, those skilled in the art will readily appreciate that many modifications are possible in the exemplary embodiments without materially departing from the novel teachings and advantages of this invention. Accordingly, all such modifications are intended to be included within the scope of this invention as defined in the claims. In the claims, means-plus-function clauses, where used, are intended to cover the structures described herein as performing the recited function and not only structural equivalents but also equivalent structures. Therefore, it is to be understood that the foregoing is illustrative of the present invention and is not to be construed as limited to the specific embodiments disclosed, and that modifications to the disclosed embodiments, as well as other embodiments, are intended to be included within the scope of the appended claims. The invention is defined by the following claims, with equivalents of the claims to be included therein. 

1. A method for sealing flat roll stock into shaped casing for encasing target products, comprising: forming tubular casing from flat roll stock; automatically moving the tubular casing using a film drive assembly with drive belts powered by at least one servomotor; electronically generating a signal associated with when additional sealed casing is needed using a sensor assembly residing downstream of the film drive assembly based on a tautness of the sealed film proximate the sensor assembly; then electronically directing the at least one servomotor to increase film-drive speed.
 2. The method of claim 1, wherein the directing is carried out to increase film drive speed for a short time of less than one second in response to a generated signal to thereby temporarily increase casing production speed and avoid a need for an excess amount of tubular casing in a buffer.
 3. The method of claim 1, wherein the short time is between about 0.1 ms and 5 ms.
 4. The method of claim 1, wherein the increase in film-drive speed is instantaneous with when the signal is generated, and wherein the increase in film-drive speed is above an immediately prior average film drive speed used for automatically moving the tubular casing.
 5. The method of claim 1, wherein the sensor assembly comprises a follower that contacts an outer surface of the tubular casing, wherein the electronically generating is carried out using the follower, and wherein the follower pivots when the tubular casing increases in tautness to cause the signal to be generated to thereby indicate a need for additional sealed casing.
 6. The method of claim 5, wherein the sensor assembly comprises an elongate flag member that reciprocates over a proximity sensor based on movement of the follower to generate the signal that causes the electronically directed increase in film drive speed.
 7. The method of claim 1, further comprising monitoring for a number of generated signals and generating an alert when there are a plurality of signals within a defined time period to thereby indicate a potential equipment malfunction and/or need for adjustment.
 8. The method of claim 1, further comprising monitoring for tubular casing pulled upstream of the sensor assembly using a sensor or encoder upstream of the sensor assembly in a direction closer to a clipper, the clipper having a voider assembly for providing a voiding operation on tubular packaging prior to clipping, wherein the sensor or encoder monitors tubular casing pulled by it.
 9. The method of claim 1, wherein the sensor or encoder is a rotatable encoder that contacts an outer surface of the tubular casing, the method further comprising allowing operation in an intermittent or continuous run mode, wherein, in the intermittent mode, the encoder is used to detect when tubular casing is being pulled during filling and during voiding, encoder movement is not used to direct the film drive system to supply a defined amount of tubular casing but instead a defined amount of tubular casing is supplied and input from the sensor assembly is deactivated or overridden, and wherein, in the continuous mode, tubular casing is supplied at a defined speed that is adjusted every defined number of cycles based on an amount of tubular casing pulled as detected by the encoder, and wherein film drive speed can be adjusted based on input from the sensor assembly associated with tubular casing tension and/or tautness, and wherein, during voiding, the sensor assembly may be used and/or a defined length of tubular casing can be supplied to accommodate for tubular casing used during voiding.
 10. The method of claim 1, wherein the sensor assembly has a follower that resides between first and second longitudinally spaced apart casing contact members held on a horn residing inside a sealed tubular casing, wherein the electronically generating is carried out using the follower, wherein the follower contacts an outer surface of the tubular casing and pivots when the tubular casing increases in tautness to directly or indirectly generate the signal.
 11. The method of claim 10, wherein the follower comprises a downwardly curved shape and an upper surface thereof abuts an outer surface of the tubular casing.
 12. The method of claim 10, wherein the first and second casing contact members are configured to have downwardly extending lobes configured so that a lower surface of the contact members extends a greater distance beyond an outer diameter of the horn than an opposing upper surface.
 13. An apparatus for packaging products using tubular casings formed from flat roll stock for encasing products therein, comprising: a horn; a forming collar residing about the horn, the forming collar configured to cooperate with a roll of flat casing material to force the flat casing material to take on a shape with long edge portions of the casing material residing proximate each other; a seal assembly held a longitudinal distance in front of the forming collar in cooperating alignment with the horn; a film drive system residing proximate the seal assembly in communication with the horn, wherein the film drive system comprises at least one servomotor; and a sensor assembly residing upstream of the film drive system in communication with the film drive system, wherein the sensor assembly is configured to generate a signal associated with an increase in tautness of tubular casing associated with a deficient amount of tubular casing relative to a tautness associated with a sufficient amount of tubular casing to cause the film drive system to increase film-drive speed.
 14. The apparatus of claim 13, wherein the film drive speed is increased for a short time of less than one second in response to a respective generated signal to thereby temporarily increase production speed and avoid a need for an excess amount of tubular casing in a buffer.
 15. The system of claim 13, wherein the short time is between about 0.1 ms and 5 ms.
 16. The system of claim 13, wherein the increase in film-drive speed is instantaneous with when the signal is generated, and wherein the increase in film-drive speed is above an immediately prior film drive speed.
 17. The system of claim 13, wherein the sensor assembly comprises a follower that contacts an outer surface of the tubular casing, wherein the sensor assembly is configured to generate the signal using the follower, and wherein the follower pivots when the tubular casing increases in tautness to cause the signal to be generated to indicate a need for additional sealed casing.
 18. The system of claim 16, further comprising an elongate flag member that is attached to the follower and reciprocates over a proximity sensor based on movement of the follower to generate the signal that causes the increase in film drive speed.
 19. The system of claim 16, further comprising a controller that monitors for a number of generated signals within at least one defined time period to thereby indicate a potential equipment malfunction or need for adjustment, and wherein the controller is configured to generate an alert when there are a plurality of detected signals with the at least one defined time period.
 20. The system of claim 13, further comprising at least one sensor or encoder upstream of the sensor assembly to monitor when casing is pulled by it or them.
 21. The system of claim 13, further comprising: a clipper with a voider assembly residing upstream of the sensor assembly proximate a discharge end of the horn; and at least one controller in communication with the at least one servomotor of the film drive assembly, the sensor assembly and the voider assembly, wherein the at least one controller is configured to control timing of a voiding operation to deactivate or override the sensor assembly signal during a voiding operation and to direct the film drive assembly to advance a fixed length of tubular casing during a respective voiding operation.
 22. The system of claim 13, further comprising at least one controller configured to allow the film drive system to have selectable intermittent or continuous run modes.
 23. The system of claim 13, further comprising first and second longitudinally spaced apart casing contact members held on the horn residing inside a sealed tubular casing proximate the sensor assembly, wherein the sensor assembly comprises a follower that contacts an outer surface of the tubular casing and pivots when the tubular casing increases in tautness to directly or indirectly generate the signal.
 24. The system of claim 23, wherein the follower comprises a downwardly curved shape and an upper surface thereof abuts an outer surface of the tubular casing.
 25. The system of claim 23, wherein the first and second casing contact members are configured to have downwardly extending lobes configured so that a lower surface of the contact members extends a greater distance beyond an outer diameter of the horn than an opposing upper surface.
 26. The system of claim 13, further comprising a bracket assembly having laterally extending slots and longitudinally extending slots, the sensor assembly held by the bracket assembly, wherein the sensor assembly comprises a follower that resides on one side of the bracket assembly attached to a flag member residing on an opposite side of the bracket assembly with a shaft laterally extending through a longitudinally extending slot, the bracket assembly holding a sensor that generates a signal when the follower is pushed down by an increase in tautness of film and pivots to rotate the shaft to move the flag member over the sensor to thereby generate the signal.
 27. The system of claim 26, further comprising a clipper with a voider assembly residing upstream of the sensor assembly proximate a discharge end of the horn, wherein the bracket assembly also holds an encoder at a level above the follower and at a distance apart from the follower, closer to the clipper, wherein the encoder resides above the horn and the follower resides below the horn.
 28. A computer program product for operating a packaging apparatus that can accommodate different casing materials and different horn diameters to provide encased elongate products, the computer program product comprising: a non-transitory computer readable storage medium having computer readable program code embodied in said medium, said computer-readable program code comprising: computer readable program code configured to provide a plurality of different predetermined operational modes for an apparatus that releaseably mounts different diameter horns and respective different size forming collars to supply different sized tubular casings from flat roll stock; computer readable program code configured to detect a signal from a sensor assembly residing upstream of a film drive assembly having at least one servomotor that powers the film drive assembly, wherein the signal is associated with an increase in tautness of tubular casing from a tautness associated with an average production film drive speed; and computer readable program code configured to direct at least one servomotor to increase film speed relative to an immediately prior film speed. 29-32. (canceled)
 33. A packaging system using flat roll stock sealed into shaped casing for encasing target products, comprising: a horn; a forming collar residing about the horn, the forming collar configured to cooperate with a roll of flat casing material to force the flat casing material into a defined shape; a casing sealer held a longitudinal distance in front of the forming collar; a film drive system residing proximate the casing sealer in communication with the horn, wherein the film drive system comprises at least one servomotor; a sensor assembly residing upstream of the film drive system in communication with the film drive system, wherein the sensor assembly is configured to generate a signal associated with an increase in tautness of tubular casing associated with a deficient amount of tubular casing relative to a tautness associated with a sufficient amount of tubular casing to cause the film drive system to increase film-drive speed; and at least one processor configured to detect a respective generated signal from the sensor assembly based on a tautness of the sealed film proximate the sensor assembly then instantaneously direct the at least one servomotor to increase drive speed, wherein, optionally, the casing sealer is a heat-seal heater.
 34. (canceled) 